Thermostatic



March 29, 1960 c. F. MuscA-ro 2,930,365

THERMOSTATIC IGNITION SWITCH Filed May l, 1958 IGNITION SWITCH BATTERY DSTRI BUTOR IN VENTOR.

CARMELO MuscATo `293.0,365 Trieansrmcienmon Carmelo V'F. VlVIusca'to, iLivonia Center, N.Y. Application May 1, 1958, Serial No. 732,364

2 Claims. (Cl. 123--41.15)

This invention relates to a safety switch for an internal combustion engine with a water cooling system, and particularly, for an automotive engine.

While automotive vehicles are provided with temperature gauges, it not infrequently happens that the driver ignores or does not notice the gauge, and the vehicle overheats, so that the engine is damaged.

Moreover, when the cooling system contains certain types of antifreeze, the antifreeze simply'boils olf at a constant temperature and it may not cool the engine effectively in so doing. When it is all gone or nearly all gone, a critical situation will arise rapidly for which the operator may be completely unprepared.

One object of the present invention is to provide a safety switch that will prevent damage to engines caused by overheating, whether the overheating is noticed'by the operator or not.

Another object of the invention is to provide a safety switch that will eliminate the factor of human judgment in determining whether an engine is overheated.

Another object of the invention is to provide a safety Vswitch that can be adjusted to stop a liquid-cooled engine at any predetermined temperature of the cooling liquid.

'l'nited States Patent] lice sensitive e1ement^22, lthat are secured"together respectively `to the two terminals -13, l18 ,ofthe-switch by an insulated rivet 23. The rtwoterminals' 13, 118 are electn'- cally linsulated by insulating washersf24 that aredisposed respectively at opposite :sides-,of Ya metal spacer .2.5. The

elements 2122 are electrically .insulated Afrornthen'vet 23 byinsulating washers 26. Contacts 27, 28am-mounted .in confrontingV relation between theopposedtips jatthe housing 15 is preferably made of a highly heat conductive metal, and its, reduced second extension 19 closely snrrounds the two elements 21, 22, so that the bimetallic element 22 responds quickly to temperature changes of the some preselected temperature, such as, for example, 200

E., and spaced apart, as shown, at and above this temperature. When the heat exchange liquid L attains a temperature of 200 F. or higher, the bimetallic element 22 moves to separate thecontact points 27, 28, and to ciently below'200 F. to permit the contact points'27, 28,

Another object of the invention is to provide a safety switch for a liquid-cooled internal combustion engine that will prevent the engine from being operated at any temperature of the cooling liquid above a predetermined temperature, regardless of the judgment of the operator.

Other objects ofthe invention will be apparent hereinafter from the specification and from therecital of the appended claims. j ,Y

The drawing is a schematic diagram showing a safety switch for the internal combustion engine of an automotive vehicle, connected in the ignition switch circuit, according to one embodiment of this invention, and shown in its open position in which the engine is stopped.

Referring to the drawing, 10 denotes an ignition switch of conventional type for an automotive vehicle engine. One electrical lead 11 from the ignition switch is connected to the battery and the other electrical lead 12 is connected to one terminal 13 of a thermostatic switch 14. The switch 14 is mounted to measure the temperature of the liquid L in the cooling system of the vehicle.

The switch 14 comprises an elongate housing 15 that is generally cup-shaped and that is formed with a first reduced, threaded extension 16 that can be threaded into a threaded recess in a Vwall 17 of the radiator or engine block or other part of the cooling system of the vehicle. The housing 15 is also formed with a second extension 19 of even further reduced diameter, that extends further into the cooling liquid L in the coolingsystem.

The terminals 13 and 18 respectively of the switch are mounted, in spaced relation, in a plug 20 of insulating material that is lodged in the bore of the housing 1 4 at its outer end. The plug 20 seals the housing 14 to form a closed chamber within the housing, within which the switch elements are mounted. The switch elements comprise a rigid metallic member 21, and a bimetallic, heatto make contact'again.

This device eliminates the factor of human judgment as to whether an engine is overheated, since it automatically stops the engine at and above some preselected temperature. Furthermore, the device operates to stop the engine when the cooling liquid L is overheated for any reason, such as, for example, when an insuicient quantity of cooling liquid is in the cooling system to effect proper heat exchange. Preferably, a standard type of thermostat switch is employed that can be adjusted readily to any safe, preselected temperature.

j While the invention has been described in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or -adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known ory potential, an ignition switch, and a distributor arranged i in series said control comprising a heat sensitive switch that is electrically connected in said ignition system circuit in series with said ignition switch andthat is mounted to sense the temperature of the crculating fluid in said cooling system, said heat sensitive switch beingvnormally closed at temperatures Vbelow a preselected temperature to permit completion of said ignition system circuit andl to permit operation of said engine, and being adapted to open at temperatures at and above said preselected temperature to open said ignition system circuit and prevent operation of said engine.

2. A safety control for an automobile engine that has a circulating fluid cooling system and an electrick ignition system circuit, said ignition system lcircuit including a 2,930,365 .Patented .Mesi-tala?? distributor in series, said controlcomprising a Huid-tight housing that is mounted in-direct contact with the uid in said cooling system and to project into a circulation path of s'aid uid,saidhousing having a chamber therein, a pair of electrically conductive elements mounted 4in said chamber at least one of which is heat sensitive to sense the temperature of the uid, each of said elements being secured in said housing at one of its ends, said elements having confronting tips at their respective free ends for 10 electrical contact with each other, said elements being connected in said electric ignition system circuit in series with said ignition switch, said elements being adjusted so that at temperatures of said fluid below a preselected temperature said tips are in electrical contact to permit completion of said ignition system circuit and to permit operation of said engine, and so that at temperatures at and above said preselected temperature said tips are not in electrical contact to open said ignition system circuit and prevent operation of said engine.

UNITED STATES PATENTS 1,219,646 Kybllrg Mar. 20, 1917 

